syzbot


VFS: Busy inodes after unmount (use-after-free)

Status: upstream: reported C repro on 2023/01/25 10:43
Labels: btrfs (incorrect?)
Reported-by: syzbot+0af00f6a2cba2058b5db@syzkaller.appspotmail.com
First crash: 132d, last: 7m

Cause bisection: failed (error log, bisect log)
Discussions (4)
Title Replies (including bot) Last reply
[syzbot] Monthly btrfs report (May 2023) 0 (1) 2023/05/30 08:21
[syzbot] Monthly btrfs report (Apr 2023) 0 (1) 2023/04/27 10:13
[syzbot] [btrfs] Monthly Report 1 (2) 2023/03/27 13:42
[syzbot] [btrfs?] VFS: Busy inodes after unmount (use-after-free) 0 (1) 2023/01/25 10:43
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-54 VFS: Busy inodes after unmount (use-after-free) C 4 41d 97d 0/2 upstream: reported C repro on 2023/02/25 22:19
linux-6.1 VFS: Busy inodes after unmount (use-after-free) 17 12d 76d 0/3 upstream: reported on 2023/03/18 09:53
android-5-15 VFS: Busy inodes after unmount (use-after-free) origin:downstream C error 2 25d 96d 0/2 upstream: reported C repro on 2023/02/26 00:11
android-5-10 VFS: Busy inodes after unmount (use-after-free) C done inconclusive 1 97d 97d 0/2 upstream: reported C repro on 2023/02/25 23:03
linux-5.15 VFS: Busy inodes after unmount (use-after-free) origin:upstream C 22 1d01h 75d 0/3 upstream: reported C repro on 2023/03/19 11:46

Sample crash report:
VFS: Busy inodes after unmount of loop0 (btrfs)
------------[ cut here ]------------
kernel BUG at fs/super.c:502!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 4997 Comm: syz-executor126 Not tainted 6.4.0-rc2-syzkaller-00163-g2d1bcbc6cd70 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023
RIP: 0010:generic_shutdown_super+0x3bb/0x480 fs/super.c:502
Code: 6b 28 48 89 ea 48 c1 ea 03 80 3c 02 00 0f 85 c4 00 00 00 48 8b 55 00 48 8d b3 a8 06 00 00 48 c7 c7 20 ca 5b 8a e8 d5 99 81 ff <0f> 0b e8 3e 7d f0 ff e9 6a fc ff ff e8 34 7d f0 ff e9 f1 fd ff ff
RSP: 0018:ffffc900039afd58 EFLAGS: 00010282
RAX: 000000000000002f RBX: ffff888022c9c000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8168b8fc RDI: 0000000000000005
RBP: ffffffff8ce8c1e0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000000 R11: 0000000000000001 R12: ffff888022c9c7d8
R13: 0000000000000000 R14: 0000000000000000 R15: ffff8880187456c0
FS:  0000555555f2e300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f89803b68e5 CR3: 0000000075cde000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 kill_anon_super+0x3a/0x60 fs/super.c:1107
 btrfs_kill_super+0x3c/0x50 fs/btrfs/super.c:2138
 deactivate_locked_super+0x98/0x160 fs/super.c:331
 deactivate_super+0xb1/0xd0 fs/super.c:362
 cleanup_mnt+0x2ae/0x3d0 fs/namespace.c:1177
 task_work_run+0x16f/0x270 kernel/task_work.c:179
 ptrace_notify+0x118/0x140 kernel/signal.c:2369
 ptrace_report_syscall include/linux/ptrace.h:411 [inline]
 ptrace_report_syscall_exit include/linux/ptrace.h:473 [inline]
 syscall_exit_work kernel/entry/common.c:252 [inline]
 syscall_exit_to_user_mode_prepare+0x129/0x220 kernel/entry/common.c:279
 __syscall_exit_to_user_mode_work kernel/entry/common.c:284 [inline]
 syscall_exit_to_user_mode+0xd/0x50 kernel/entry/common.c:297
 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f24e2be0d27
Code: 07 00 48 83 c4 08 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc4968b128 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 000000000000b4bb RCX: 00007f24e2be0d27
RDX: 00007ffc4968b1e8 RSI: 000000000000000a RDI: 00007ffc4968b1e0
RBP: 00007ffc4968b1e0 R08: 00000000ffffffff R09: 00007ffc4968afc0
R10: 0000555555f2f633 R11: 0000000000000206 R12: 00007ffc4968c250
R13: 0000555555f2f5f0 R14: 00007ffc4968b150 R15: 0000000000000010
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:generic_shutdown_super+0x3bb/0x480 fs/super.c:502
Code: 6b 28 48 89 ea 48 c1 ea 03 80 3c 02 00 0f 85 c4 00 00 00 48 8b 55 00 48 8d b3 a8 06 00 00 48 c7 c7 20 ca 5b 8a e8 d5 99 81 ff <0f> 0b e8 3e 7d f0 ff e9 6a fc ff ff e8 34 7d f0 ff e9 f1 fd ff ff
RSP: 0018:ffffc900039afd58 EFLAGS: 00010282
RAX: 000000000000002f RBX: ffff888022c9c000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8168b8fc RDI: 0000000000000005
RBP: ffffffff8ce8c1e0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000000 R11: 0000000000000001 R12: ffff888022c9c7d8
R13: 0000000000000000 R14: 0000000000000000 R15: ffff8880187456c0
FS:  0000555555f2e300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f89803b68e5 CR3: 0000000075cde000 CR4: 0000000000350ef0

Crashes (699):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Manager Title
2023/05/19 13:28 upstream 2d1bcbc6cd70 3bb7af1d .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-root VFS: Busy inodes after unmount (use-after-free)
2023/05/01 15:21 upstream 58390c8ce1bd 62df2017 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-root VFS: Busy inodes after unmount (use-after-free)
2023/05/01 02:32 upstream 825a0714d2b3 62df2017 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-root VFS: Busy inodes after unmount (use-after-free)
2023/03/31 05:49 upstream 8bb95a1662f8 f325deb0 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/23 13:15 linux-next 715abedee4cd 4bce1a3e .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-linux-next-kasan-gce-root VFS: Busy inodes after unmount (use-after-free)
2023/03/31 04:56 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 59caa87f9dfb f325deb0 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-gce-arm64 VFS: Busy inodes after unmount (use-after-free)
2023/01/24 11:34 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci edb2f0dc90f2 9dfcf09c .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-gce-arm64 VFS: Busy inodes after unmount (use-after-free)
2023/06/02 22:19 upstream 9e87b63ed37e a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root VFS: Busy inodes after unmount (use-after-free)
2023/06/02 20:40 upstream c43a6ff9f93f a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/06/02 19:15 upstream c43a6ff9f93f a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/06/02 02:12 upstream 1874a42a7d74 a4ae4f42 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream VFS: Busy inodes after unmount (use-after-free)
2023/06/01 20:45 upstream 929ed21dfdb6 a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root VFS: Busy inodes after unmount (use-after-free)
2023/06/01 19:25 upstream 929ed21dfdb6 babc4389 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/06/01 16:23 upstream 929ed21dfdb6 babc4389 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/06/01 09:41 upstream 48b1320a674e babc4389 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/06/01 00:35 upstream 48b1320a674e e2a77acd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root VFS: Busy inodes after unmount (use-after-free)
2023/05/31 17:09 upstream afead42fdfca 09898419 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/31 08:38 upstream afead42fdfca 09898419 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/31 07:05 upstream afead42fdfca 09898419 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/30 09:55 upstream 8b817fded42d cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/30 06:56 upstream 8b817fded42d cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/30 05:05 upstream 8b817fded42d cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/30 03:28 upstream 8b817fded42d cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/28 22:21 upstream 416839029e38 cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/28 20:08 upstream 416839029e38 cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/28 07:45 upstream 4e893b5aa4ac cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root VFS: Busy inodes after unmount (use-after-free)
2023/05/28 05:03 upstream 4e893b5aa4ac cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/28 00:21 upstream 49572d536129 cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root VFS: Busy inodes after unmount (use-after-free)
2023/05/27 19:05 upstream 49572d536129 cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/27 14:18 upstream 49572d536129 cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/27 12:40 upstream a92c9ab69f66 cf184559 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream VFS: Busy inodes after unmount (use-after-free)
2023/05/27 10:57 upstream 91a304340a22 cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root VFS: Busy inodes after unmount (use-after-free)
2023/05/27 09:48 upstream 91a304340a22 cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root VFS: Busy inodes after unmount (use-after-free)
2023/05/27 02:34 upstream 0d85b27b0cc6 cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/26 17:08 upstream 9db898594c54 b40ef614 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/26 08:19 upstream 9db898594c54 b40ef614 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/25 01:17 upstream 933174ae28ba 4bce1a3e .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream VFS: Busy inodes after unmount (use-after-free)
2023/05/24 20:18 upstream 9d646009f65d 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root VFS: Busy inodes after unmount (use-after-free)
2023/05/24 17:39 upstream 9d646009f65d 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/24 10:20 upstream 27e462c8fad4 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/24 09:05 upstream 27e462c8fad4 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root VFS: Busy inodes after unmount (use-after-free)
2023/05/23 16:55 upstream ae8373a5add4 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/23 03:44 upstream 421ca22e3138 4bce1a3e .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream VFS: Busy inodes after unmount (use-after-free)
2023/05/23 01:48 upstream 421ca22e3138 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/22 20:22 upstream 44c026a73be8 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/22 16:39 upstream 44c026a73be8 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root VFS: Busy inodes after unmount (use-after-free)
2023/05/22 07:31 upstream e2065b8c1b01 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/22 02:51 upstream e2065b8c1b01 4bce1a3e .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream VFS: Busy inodes after unmount (use-after-free)
2023/05/22 00:57 upstream e2065b8c1b01 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/21 21:28 upstream e2065b8c1b01 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/21 17:53 upstream 0dd2a6fb1e34 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/21 15:35 upstream 0dd2a6fb1e34 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs VFS: Busy inodes after unmount (use-after-free)
2023/05/21 08:36 upstream 0dd2a6fb1e34 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root VFS: Busy inodes after unmount (use-after-free)
2023/05/30 15:04 upstream 8b817fded42d 8d5c7541 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 VFS: Busy inodes after unmount (use-after-free)
2023/05/29 23:46 upstream 8b817fded42d cf184559 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 VFS: Busy inodes after unmount (use-after-free)
2023/05/29 02:59 upstream 7877cb91f108 cf184559 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 VFS: Busy inodes after unmount (use-after-free)
2023/06/01 22:37 linux-next 715abedee4cd a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root VFS: Busy inodes after unmount (use-after-free)
2023/05/31 20:16 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci eb0f1697d729 e2a77acd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 VFS: Busy inodes after unmount (use-after-free)
2023/05/29 05:07 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci eb0f1697d729 cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 VFS: Busy inodes after unmount (use-after-free)
2023/05/27 00:24 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci eb0f1697d729 cf184559 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 VFS: Busy inodes after unmount (use-after-free)
* Struck through repros no longer work on HEAD.